Despite the work by Bos et al. reported in Blood and by other researchers on the structure and function of the procoagulant molecules, the pathophysiology of venom-induced consumption coagulopathy (VICC) associated with human envenoming by these snakes remains unclear. Although it would appear that the presence of a factor Va–like toxin in brown snake (Pseudonaja spp) venom that is impervious to regulation by the hemostatic system provides a potent biologic weapon against prey and in human envenoming, clinical research does not fully support this.